A Brief Note on Handmade vs. Cast Rings
There is a mountain of information you would need to take in and process before making a purchase, including the qualities of the gem, the metal used in the band, and whether or not your 1.25-carat diamond ring is handmade.
The best thing about handmade rings is that they do not carry the same amount of porosity that cast rings do. Porosity is essentially tiny bubbles resulting in pockmarks, which can sometimes weaken the ring. Another issue with cast rings is that the mold is required to be a bit thicker so that diamonds can be set into the band, such as in the case of a pave design.
Moreover, the design is hardly ever unique; you would probably find it on the finger of more than one other person. Custom diamond rings are generally made directly out of gold or platinum, and there, the proportions need to be kept precise to a very high degree.